Both what you eat and when you eat are important. Insulin has been identified as a primary signal that helps communicate the timing of meals to the cellular clocks located across our body, commonly known as the body clock. So eating at specific times or taking drugs that target insulin signalling can be beneficial to health.

The body clock which is also known as the circadian rhythm is a 24-hour biological cycle that occurs individually in every cell of the body, driving daily rhythms in our physiology, from when we sleep, to hormone levels, to how we respond to medication. Our body clock is synchronised with the surrounding environment by exposure to daylight and the timing of meals. This synchrony is important for long-term health, and it is well known that disrupting your circadian rhythm by shift work or travel across time zones can be detrimental for health. Importantly, it is thought that eating at unusual times, as often occurrs during shift work and jet lag, is a major cause of body clock disruption. However, it has not previously been established exactly how the body clock senses and responds to meal timing, making it difficult to provide medical advice or interventions that might alleviate the problem.

So now insulin has been identified as a primary signal that helps communicate the timing of meals to the cellular clocks across our body, and in doing so strengthen the circadian rhythm. At the heart of these cellular clocks is a complex set of molecules whose interaction provides precise 24-hour timing. When insulin is provided at the wrong biological time, it disrupts normal circadian rhythms.

The modern society poses many challenges to our health and wellbeing, things that are viewed as commonplace, such as shift-work, sleep deprivation, and jet lag, disrupt our body clock. It is now becoming clear that circadian disruption is increasing the incidence and severity of many diseases, including cardiovascular disease and type 2 diabetes.

The wrong times could have a major impact on our circadian rhythms. So paying particular attention to meal timing and light exposure is likely the best way to mitigate the adverse effects of shift-work. Even for those who work more traditional hours, being careful about when we eat is an important way to help maintain healthy body clocks, especially as we age.